What is an inode?

inode (index node)inode - Wikipedia, the free encyclopedia
An inode is a data structure on a traditional Unix-style file system such as UFS or ext3. An inode stores basic information about a regular file, directory, or other file system object. A POSIX filesystem includes things like size in bytes, deviceid,userid,guid,filemode,timestamps,linkcounts,pointers to disk blocks.
File names and directory implications:

inodes do not contain file names, only other file metadata.

Unix directories are lists of association structures, each of which contains one filename and one inode number.

The file system driver must search a directory looking for a particular filename and then convert the filename to the correct corresponding inode number.